@713j
Not @gloaming so hope you don't mind me passing on what the Director or electrophysiology at Mayo Jacksonville told me.

In his experience and research the Citrate is the most digestible and what he recommends. In his words some experience digestive issues (loose bowels) with citrate but again he said some.

He advised if that occurred he recommended Glycinate as also was highly absorbable. Not my research or opinion but from an EP that has written several books, heavily involved with research, and does seminars around the world. And to add to that he is the President of the Electrophysiology Medical Group Society.